Vehicle braking system.



w. 0001mm. VEHICLE BRAKING SYSTEM. APPLICATION I'IILBD 001'. 8, 1905.RENEWED D30. 14, 1908.'

Patented Sept. 12, .1911.

ATTORNEY UNITED STATESv PATENT OFFICE WILLLAI coornn, or wrLKI snuno,PENNSYLVANIA, ASSIGNOR, BY mns'nn ASSIGN- mnnrs, To run wns'rmo ousn AIRBRAKE COMPANY, A conroan'rron or PENN- SYLVANIA.

VEHICLE BRAKING SYSTEM.

Specification of Letters I'at ent. Patented Se t, 12, 1911.

Application filed October 3, 1905, Serial No. 281,190. Renewed December14, 1908. Serial No. 467,540.

Tb all whom it may concern:

Be it known that 1, WILLIAM Coornn, a citizen of the United States, anda resident of Wilkinsburg, in the county of Allegheny and State ofPennsylvania, have invented a new and useful Improvement in VehicleBraking Systems, of which the following is a specification.

My invention relates to vehicle braking systems, and it has specialreference to means for governing a' plurality of independent systems ofautomatic brake pressure regulation which'are adapted for application tothe several units of a railway train and are capable of multiplecontrol.

The object of my invention is to provide sim le and reliable means forautomatically a p ying the brakes on one or more vehicles w ich form asection of a train equi ped as above indicated and which have, or anyreason, been separated from the forward section of the train of whichthey were a art. p In order to avoid destructive accidents in case atrain of cars is inadvertently broken into sections, it is desirable toautomatically bring the detached section to rest by setting the-brakeson the cars which are separated from the control center. Hitherto thisresult has been accomplished in vehicle trains which are equipped withpneumatic braking systems by means dependent upon the rupture of a fluidsupply pipe which usually forms a continuous connection from a reservoiror a compressor on one of the vehicles to receiving tanks on all of theothers. For the accomplishment of this result in trains of electricvehicles which are capable of' multiple operation and are provided withindependent braking systems, I have provided automaticmeans dependentupon the rupture of a train line conductor through which the severalunits are simultaneously controlled, for effecting the immediateapplication of an emergency brake on the detached section of the train.

Figures 1 and 2 of the accompanying drawings illustrate a convenientmeans for carrying out my invention and are diagrammatic views,respectively, of a single, typical car equipment and partial electricalconnections for several vehicles similarly equipped.

Referring to the drawings, a brake cylinder 1 is supplied with fluidpressure from I a pressure storage tank 2 through a pipe 3,

when pressure is applied through the valve 7 the piston is forced intosuch a position that connection from the cylinder to the valves 4 and 9is cut ofi', while connection from the valve 7 to the cylinder iscompleted. An outlet is provided between the 7 cylinder 1 and the checkvalve 5 through a branch pipe 8 and a release valve 9. The admissionvalve 4, the release valve 9 and the emergency valve 7 are respectivelyactuated by electro-magnet coils 10, 11 and 12, and 13. Electricalenergy is supplied to the magnet coils through a controller 14 which isadapted to occupy a plurality of positions a, b, c, d, and e andobviously may be combined with any well known form of electric vehiclecontroller to constitute the braking notches. The magnet coils 10, 12and 13 are supplied with energy at a substantiallyconstant potentialfrom any convenient source such as a battery 15, while the coil 11 ofthe valve 9 is supplied with energy from a motor 16 that may preferablybe one of the motors of a vehicle equipment which is'run as a generatorduring the braking period. its field magnet windings being energizedfrom a constant potential source or the residual magnetism of its fieldmagnets being relied upon for the initial field excitation.

The motor 16 may be arranged in any well known manner to drive thewheels 17 of the vehicle to which the equipment is ap-- plied and brakeshoes 18 may be so connected to a piston 19 which operates in thecylinder 1, by meansof a piston rod 20 and the intermediate levers 2 1.that the fluid pressure in the-cylinder forces the shoes into engagementwith the peripheries of the wheels and gives the desired braking eflect.

'When-it becomes desirable to apply the brakes the controller 14 ismoved from a position a through the position b to the position 0 when acircuit is completed from through a contact finger 23, ring se ringsegment 30 and contact finger 31 to the opposite armature terminal'32 ofthe motor 16. Circuit connections are also completed from a positiveterminal of the battery 15 through conductor 33-, contact finger 34,ring segment 35, contact finger 36 and the magnet coil 10 to thenegative terminal of the battery. The valves 4 and 9 are so arrangedthat the energizing of the magnet coil 11 closes the release valve9 andwhen the controller 14 is in the position 0 pressure is admitted fromthe tank 2 to the cylinder 1 through the check valve 5 which serves toprevent the air from exhausting therethrough when the coil 10 isdeenergized. Under ordinary circumstances the controller 14 is thenmoved to the position b so that the coil. 10 is deenergized and the coil11 is energized only by the current supplied from the motor 16 and asthe speed" of the motor decreases the voltage delivered therefrom willproportionally decrease so that the magnet, coil 11 becomesweakened'until.

pressure in the cylinder 1 is sufiicient to force the valve 9 open. Thevalve 9 is held in this open positlo-n until the pressure in finger 34,ring segment the cylinder 1 has become so reduced, relative to thestrength of the current supplied to the magnet 11, that the valve isagain closed. The operation is automatically repeated as the speed ofthe vehicle decreases until itis brought to rest and the pressure in thecylinder is reduced to 'zero. It is sometimes desirable, however, as isthe case when stopping a vehicle on a grade, to maintain the pressure inthe cylinder .1 for some considerable length of time after the vehiclehas'been brought to rest, in which case the controller 14 may be-movedto a position d when a circuit is completed from the positive batteryterminal, through the contact 35, contact finger 37 and the magnet coil12 of the valve 9 to the negative battery terminal. The energizing ofthe magnet coil 12 holds the valve 9 closed regardless of the strengthof the coil 11 so that pressure is maintained in the .cylinder 1.

When it becomes desirable to apply full pressure to the brakes verysuddenly, as in case of accident, the controller 14 is moved totheposition e which releases the valve 7 and admits full pressure fromthe tank 2 to the cylinder 1. The emergency valve 7 is normally heldclosed by the actuation of the magnet coil 13 which is continuouslyenergized from the battery 15 while .the controller 14 occupies theseveral positions a, b, c, 'and d, connections being completed thebrakes to the whole train as herein fore explained for asingleequipment, the

from the positive battery terminal through conductor 33,- contact finger34, ring segment 35, contact finger 38, conductors 39 and 40 to themagnet coil 13 andthe negative battelky terminal.

hen several vehicles which are similarly.

equipped with electrically controlled pneumatlc braking systems, thecontroller onthe forward vehicle which is used as a master switch isoperated to simultaneously apply valves being interconnected by a trainin a well known manner.

Since my invention relates particularly to emergency brake applicationsI deem it unnecessary to show complete train line connections foroperating the application and release valve magnets but I have shown inFig. 2 the electrical connections for a plural1ty of units equipped withemergency brake magnets, the several units being interconnected by aplurality of train line conductors 39 and 41. The several controllersexclusive of the one which is used as amaster switch occupy the positione in which position the contact fingers 34 and 38 are movedout of engaement with the ring segments 35 so that tfie emergency valve magcircuitconnections for the several magnet me net windings 13 are deenerglzedand the all the emergency valve magnet windings are energized as long asthe master switch occupies positions a, b, 0 and d, and the train lineconductors 39 and 41 remain intact. If, however, one or more units ofthe train become disconnected from theremaining portion on which themaster switch is located such units are quickly brought to rest by theapplication of fluid pressure through the emer ency valve, since thevalve magnet circuit is Interrupted by the rupture of conductors 39 and41. Th valves may all be applied by master controller 14 will of theoperator.

The connections for the valve magnets may obviously bevaried withoutdeparting from the spirit of my invention and I desire that suchvariations shall be included within its scope.

I claim as my invention: a 1. In a fluid braking system for electricvehicles, the combination with an electricallycontrolled release valve,and means'for automatically varying the voltage applied moving the toposition e at the e emergency to the valve magnet, of an emergencyapplication valve, and means dependent upon its operation for renderingthe release valve inoperative.

2. In a fluid braking system for electric motor-driven vehicles, thecombination with an electrically operated release valve which isdependent for its action upon the current delivered from one or moremotors of the vehicle equipment during the braking period, of anemergency application valve, and meansdependent upon the operation ofthe emergency valve for rendering the release valve inoperative.

3. In a fluid-pressure braking system, the combination with an admissionvalve, and an exhaust valve, of an emergency application valve, andmeans dependent upon the operation of the emergency valve for renderingthe admission and exhaust valves inoperative.

4. In a fluid-pressure vehicle braking system, the combination with anadmission valve, and an electrically operated release valve which isautomatically dependent upon the action of the vehicle during'thebraking period, of an emergency application valve, and means dependentupon the operation of the emergency valve for rendering the admissionand exhaust valves inoperative.

5. In a fluid braking system'for electric vehicles, the combination withan admission valve, and a release valve, of means for governing theaction of said valves, of automatic means dependent upon the currentdelivered from one or more of the motors during the braking period forregulating the action of the release valve, of an emergency applicationvalve, and means dependent upon the operation of the emergency valve forrendering the admission and exhaust valves inoperative.

6. In a vehicle braking system, the combination with a brake cylinder,and electrically operated admission and exhaust valves which arerespectively opened and closed by the electrical energy, of an emergencyadmission valve, and a slide valve which severs the connection betweenthe brake cylinder and the normal admission and release valves and whichis dependent upon the operation of the emergency valve.

tems therefor each of which comprises an electrical control releasevalve, means for automatically varying the voltage applied to the valvemagnet, and an emergency admission valve, of means dependent upon itsoperation for rendering the release valve inoperative, and means forautomatically operating the braking systems upon the detachment from thetrain of one or more vehicles to stop said vehicles.

8. In a train of vehicles, the combination with a plurality ofindependent braking systems therefor each of'which comprises anadmission valve, an exhaust valve, and an emergency valve, of means forautomatically actuating the emergency valve upon the detachment from thetrain of one or more vehicles to stop said vehicles,- and meansdependent upon the operation of an emergency valve for rendering theadmission and release valves inoperative.

9. In a train of vehicles, the combination with a plurality ofindependent braking systems therefor that are electrically governed,means for normally grading the brake pressure as-the vehicles are,retarded, and a plurality of train line conductors for connecting theseveral governing units to gether, of means for automatically operatingthe braking systems, upon the detachment from the train of one or morevehicles,

to suddenly stop the detached vehicles.

10. In a train of vehicles, the combination with a plurality ofindependent braking systems therefor each comprising means forautomatically reducing the brake pressure as the vehicle is retarded,and a'series of electrically governed control systems which areconnected by a continuous train line conductor, of means independent ofsaid pressure reducing means and dependent upon the rupture of the trainline for automatically setting the brakes on a detached section of thetrain.

In testimony whereof, I have hereunto subscribed my name this 29th dayof'Sep-

